My parents have a second hand dell PC, they have the phone in a different room to the computer, but a second socket in the computer room, when they plug the telephone line from the pc to the socket in the computer room the phone goes dead. Any ideas.
Sounds like lightning may have hit the modem at one time and has shorted the phone line. Before you replace the modem, (1) check the jack wiring. Borrow another phone and plug it in. Does it work? Did the original phone go dead this time? (2) check the wire from the computer to the phone jack - it could be shorted. Borrow a phone line from a friend and try that. If the jack and wire are OK, I would suspect the modem is dead.